[U-Boot] [PATCH v1 0/4] Jetson-TK1 support for PSCI

[Ian Campbell]

On Wed, 2015-01-14 at 08:57 +0100, Thierry Reding wrote:
> > I also pushed my tree to gitorious:
> >         https://gitorious.org/ijc/u-boot jetson-psci-v1
> > 
> > I would Ack your patch, but I don't think you've posted it and it has no
> > S-o-b so that would seem a bit premature/rude of me. For the same reason
> > I've not actually included it in the series posted (but it is in the
> > gitorious branch).
> 
> Feel free to take ownership of that patch. I currently don't have the
> time to work on this and it seems you've made good progress on it.

Will do. Could you offer a S-o-b for it please so I can pick it up.

> It could probably use some cleanup because there's a bit of debug output
> still in there. Also...
> 
> > FWIW I think you could drop your stub versions of psci_cpu_off and
> > psci_cpu_suspend (assuming you don't want to implement them) since the
> > common code has stubs.
> 
> ... I'd think you'd need to implement these so that you can get proper
> suspend/resume support in the kernel. I've had to disable cpuidle (via
> #undef CONFIG_PM_SLEEP in arch/arm/mach-tegra/cpuidle-tegra114.c) in the
> kernel to make that code not powergate CPUs. Ideally I think the kernel
> would check that it's running with PSCI support and disable the cpuidle
> driver. Maybe that could be done by introducing a new cpuidle driver
> that checks for PSCI availability and uses it when present.

Hrm, I'm not sure how this all fits together, it's not a problem I've
noted before.

FWIW I think cpu_off and cpu_suspend are optional in PSCI v0.1 so an
initial version doesn't necessarily need to implement them (sunxi
doesn't for example), but as you say they do enable useful features.

> Adding Stephen and Tom for visibility.

Oops, sorry, I got them for the patches (via docs/git-mailrc) but forgot
about the cover letter.

Ian.